There are several ways to hook up rotary switching for the receiver and for both the receiver and the AADE DFD2. The easiest one is to use a 2 pole rotary with at least 4 positions, check out AADE DFD2 and Receiver Switching with 2 Sections. No rotary switches are included with the kit.

The second schematic switches the receiver and the DFD2 with a two section rotary switch. The third schematic uses a one section rotary switch but is a little more complicated to wire.

For those using the SWL version of the receiver, a three section rotary switch is used for switching the bands. Manual switching of the bands is shown in the SWL instructions.

Switching the DFD2 with the Switches on the PCB

NOTE: This is a revised schematic (date: 1/14/07). All customers who have CDROMs dated between 9/20/06 to 1/14/07 need to update with this schematic.

The base connections for the transistors have been moved from the left side of D4 and D5 to the right side between D4/D6 and D5/D7.

NOTE: D1, D2 and D3 are very important diodes and should be double checked for proper position (band away from counter) before connecting the switching circuit. These diodes protect the frequency counter PIC from 12 Volts coming from the receiver board.

If a wiring mistake was made, a transistor was bad, or any other reason, the PIC would be blown up having 12 volts on its offset pins.

D6 and D7 keep 5 volts from the counter from getting into the switching circuit of the filters and partially turning on an LED that is supposed to be off. They isolate the counter 5 volts from Board 1. If a mistake is made here, no damage is done.

The wires going to the switches from the 20/17 and 30/17 circles at the Bandpass and Crystal Filter on Board 1 are disconnected at the switches and soldered to the points labeled 20/17 Circle and 30/17 Circle on the schematic above.

There are no connections between the circles and the switches on Board 1 anymore.

The 20/17, 30/17 and 40/30 Switch labels go to the switches at the front of Board 1 in the holes labeled as noted.

This circuit is built "ground plane" style with high megohm resistors used as standoffs. You could also use a small piece of prototype printed circuit board.

This circuit is a very slow on-off switch so any type of diode and any general purpose NPN transistor can be used.

Rotary Band Switch for Receiver Only

One 4 position rotary switch - some switches found at hamfests/stores have more positions, doesn't matter, just use the first four.

Two 1N4148 diodes - not critical as to type, practically any diodes will work.

Watch out for the correct connections from the Bandpass and Crystal Filter connections. See below.

A wider view of how it all is connected.

The switches on the board can be removed if the rotary switch is used.

The rotary switch has been mounted on Board 1 with two standoffs. The space between the standoffs just accepts a standard size rotary switch.

Notice the wiring to the switch and the connections on the board.

Another place to mount the rotary is on a piece of PCB board soldered to the bottom plate.

AADE DFD2 and Receiver Switching with 2 Sections

The receiver has its own rotary section and the frequency counter has its own rotary section.

Some rotary switches have two sections on one wafer. These might be cheaper than a rotary with two wafers. Also, almost all now have more than four poles, i.e. 11, and are sold as universal rotary switches. They will work fine, just use four poles.

Remember to use an RF Choke and .01 bypass capacitor at the jumper connections of the Frequency Counter when hooking up the counter section. See picture.

AADE DFD2 and Receiver Switching with One Section

Thanks go to James Wallace of Rowlett, TX, who figured out the final schematic to make this circuit work and for his design of the schematic. James is an Electroluminescent Kit owner.

Both switching circuits are combined on one section.

The truth table for the Board Switches and Frequency Counter is the following:

Board Switches

20/17

30/17

40

Open

Open

30

Open

Gnd

20

Gnd

Open

17

Gnd

Gnd

Frequency Counter

Upper Jumper

Lower Jumper

40

Gnd

Open

30

Gnd

Gnd

20

Open

Gnd

17

Open

Open

Diodes D2 and D5 isolate the counter switching and the receiver switching from each other. When D2 was not installed the 30/17 LED would not turn completely off and the Crystal Oscillator would not switch properly.

Rotary Switch for SWL Receiver and AADE DFD2 Frequency Counter

All diodes are 1N914 or 1N4148 or similar. If you can't find a 5 position rotary switch, one with more positions may be used, just use the first five positions. There are some 11-12 position universal rotary switches that are easy to find and inexpensive in price at surplus part businesses.

Notice that a ground connection goes to the common connection on the first and third wafers (counter and filters). A 12 Volt connection goes to the common connection on the middle wafer (VFO).

Be very carefull of the Frequency Counter connections, putting 12 Volts on the jumper pins can blow the PIC.

Frequency Counter Connections

Looking at the back of the counter PCB board, the connections are made to the left pins of the jumpers (upper and lower). The right pins should show a connection to ground.

Tin the pins first, then tack solder the wires to the pins being careful to get them on straight.

Phototransistor Connection on Board 1

Photodiode Connection on Board 1

Picture shows the connection to the "Ground for 20/17" connection. This connection is at the Bandpass Filters.

The wire is soldered to the bottom of the board if the rotary switch is mounted underneath Board 1.

Picture shows the connection to the "Ground for 30/17" connection. This connection is at the Crystal Filters.

The wire is soldered to the bottom of the board if the rotary switch is mounted underneath Board 1.